Greater differences in forensic DNA profile frequencies estimated from racial groups than from ethnic subgroups

A National Research Council (NRC) report asserted that genetic diversity between subgroups within a race is greater than between races. While this is counterintuitive to the basic tenets of human population genetics, the forensic application of statistical estimates of DNA profile frequencies has been questioned. The general approach used for estimating DNA profile frequencies by the majority of North American forensic laboratories is the use of the product rule on fixed bin allele frequencies derived from general population group databases. An informal analysis of the differences in frequency estimates within Hinf I-generated RFLP data determined in three ethnically distinct population groups--Norwegians, Spanish, and Turks--and in Caucasians and Blacks from the United States is presented. The VNTR loci analyzed are D2S44, D7S21, and D12S11. The data demonstrate that the assertion by the NRC is unfounded and that major population group databases, in lieu of subpopulation databases, can be used to provide estimates of DNA profile frequencies without consequences of wrongful bias.